A set of polymorphic expressed sequence tag-derived microsatellites from the bay scallop, Argopecten irradians irradians, and their transportability in three other scallop species.

摘要

This study was conducted to develop 15 novel Argopecten irradians irradians expressed sequence tag (EST)-associated polymorphic microsatellite markers and to examine the potential use of these markers for pedigree analysis and transferability in 3 other commercially important scallop species. Polymorphism evaluation was made in bay scallop collected from Haiyang, Shandong Province, China. Of the 5381 A. irradians irradians ESTs screened, 167 sequences had microsatellite-type repeats. Of the 167 sequences, 28 were selected for microsatellite marker optimization because of repetition times priority. Of the 28 primer pairs, 15 produced single locus and polymorphic profiles of the expected size. No similarity was observed against the published EST-linked microsatellite loci for all the 15 microsatellites. Eight primer pairs produced monomorphic profiles, and five primers did not amplify any product. The number of alleles ranged between 3 at AIE004 and 14 at AIE025, with an average of 5.5. The observed and expected heterozygosities ranged from 0.000-0.781 and 0.155-0.885, respectively. The average polymorphic information content (PIC) was 0.548. The large variability exhibited by the 15 microsatellite loci analysed in this work resulted to a high power for parentage assignment. Significant departures from Hardy-Weinberg equilibrium (HWE) were observed in 8 of the 15 single locus exact tests after sequential Bonferroni correction. Insignificant pairwise linkage disequilibrium between any loci was observed. Cross species amplification was examined in 10 individuals of Chlamys farreri and Patinopecten yesoensis collected from Shandong Province and Amussium pleuronectes collected from Hainan Province. In both C. farreri and P. yesoensis, 9 loci gave successful amplifications, although only 5 loci were polymorphic. In A. pleuronectes, 3 loci produced unambiguous PCR products, but only one was variable. It was concluded that the microsatellite loci developed in this study could be used as molecular markers for various genetic studies.